# SDR ASAA2020102833440

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 28, 2020
- Submitted: October 30, 2020
- Operation: Air carrier
- Aircraft: [N440AS](https://openairdocs.org/aircraft/N440AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41705
- Aircraft time: 26,789 hours, 8,615 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Control Valve
- Part number: 3989083
- Part serial: 5296
- Condition: Leaking
- Location: Lt A/C Pack
- Part time: 66,276 hours, 25,098 cycles
- Stage of operation: CR
- How discovered: O
- Nature of condition: M, K, J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020102833440

## Discrepancy

LEFT PACK LIGHT DURING FLIGHT, EXTINGUISHES WHEN MASTER CAUTION RESET.  GROUNDED-YES.  CONFIRMED FAULT, LEFT PACK LIGHT ILLUMINATES ON RECALL.  LT PACK/ZONE TEMP CONTROLLER BITE SHOWS "SRADA INLET" FAULT.  REMOVED & REPLACED LT SRADA INLET ACTUATOR, REF AMM 21-51-21.  ALSO, FOUND LT TCV 1 (V139) OVERHEATED & LEAKING.  REMOVED & REPLACED TCV, REF AMM 21-51-10, LEAK CHECK & OPERATIONS CHECK NORMAL, REF AMM 21-61-00-700-806-002.  ACCOMPLISHED ALTERNATE DEACTIVATION PROCEDURE, REF ASA MAINTENANCE PROGRAM CHAPTER 5, SECTION 5-07-01, TABLE 3, ITEM 1.  REVERSED ALTERNATE DEACTIVATION PROCEDURE.

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